Monitoring And Controlling A Cooking Environment

ABSTRACT

Various embodiments are disclosed. A cooking vessel may include a cover, thermionic power converter, and a handle having a memory, a transmitter, and an IR light emitting diode. An infrared image sensor may be used with the IR light emitting to determine a location of the cooking vessel. A sensor and a transmitter may be disposed in the vessel cover to detect and transmit an indication of a boil condition. A system may include a sensor to detect a weight of a cooking vessel and a receiver to receive from the cooking vessel a memory-stored property of the cooking vessel, and a processing unit. The processing unit may determine a weight of the food and a predicted cooking time. The system may include a projected user interface and a proximity sensor. An apparatus may include an image sensor to capture a reference image and current images of a surface. A location of a cell on the surface may be determined from the images.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit under 35 USC Section 119(e) of U.S. Provisional Patent Application Ser. No. 61/325,088, filed Apr. 16, 2010, entitled “Projected User Interface.” The present application is based on and claims priority from this provisional application, the disclosure of which is hereby expressly incorporated herein by reference in its entirety.

FIELD

This application relates generally to monitoring a cooking process and controlling a cooking environment. More particularly, this application relates to monitoring a cooking process and controlling a cooking appliance in a safe and convenient manner.

BACKGROUND

A person preparing a meal typically uses three major work areas in a kitchen and a variety of minor areas. The three major areas are the cleaning area (sink), the cooking area (range or cooktop) and the cold storage area (refrigerator). The minor areas include storage areas for food, cookware, serving ware, and the like. Preparing a meal typically involves performing multiple tasks in these locations more or less simultaneously. Further, it is not uncommon for the person preparing the meal to also be supervising children, interacting with others located inside or outside of the kitchen, or leaving a work area or the kitchen itself for various reasons and for various lengths of time. Monitoring or controlling one or more cooking processes simultaneously can be a problem, especially if the person is not present in the cooking area.

Accordingly, there is a need for apparatus and methods for monitoring a cooking process and controlling a cooking environment. Moreover, there is a need for apparatus and methods for monitoring a cooking process and controlling a cooking appliance in a safe and convenient manner.

SUMMARY

One embodiment is directed to a cooking vessel. The cooking vessel may include a vessel handle. A memory may be disposed in the vessel handle to store a vessel parameter. A transmitter may be disposed in the vessel handle to transmit the vessel parameter. The cooking vessel may also include a thermionic power converter to provide electrical energy to the memory and transmitter. In one embodiment, the vessel handle may include at least one IR light emitting diode. An infrared image sensor and the IR light emitting may be used to determine a location of the cooking vessel. In one embodiment, the cooking vessel may include a cooking vessel cover. A sensor may be disposed in the cooking vessel cover to detect a boil condition in the cooking vessel. In addition, a transmitter may be disposed in the cooking vessel cover to transmit a message indicative of a detected boil condition.

Another embodiment is directed to a cooking vessel. The cooking vessel may include a vessel handle, which may include at least one IR light emitting diode. An infrared image sensor and the IR light emitting may be used to determine a location of the cooking vessel. The cooking vessel may also include a thermionic power converter to provide electrical energy to the IR light emitting diode. In one embodiment, at least two IR light emitting diodes are provided and arranged in a pattern in the vessel handle, the pattern corresponding with a particular one of two or more cooking vessels. Thus, the pattern may be used to identify the cooking vessel. In one embodiment, the at least one IR light emitting diode emits a particular sequence of IR light pulses identifying the cooking vessel. The at least one IR light emitting diode may emit radiation at a single frequency so as to be distinguishable from other IR radiation. In one embodiment, cooking vessel may include a cooking vessel cover. The cooking vessel cover may have a sensor and a transmitter disposed in the cover. The sensor may detect a boil condition in the cooking vessel. The transmitter may transmit a message indicative of a detected boil condition. In another embodiment, the cooking vessel may include a cooking vessel cover, which includes a vessel cover handle. The vessel cover handle may have at least one IR light emitting diode disposed in the handle. The presence of the cooking vessel cover is determined if an infrared image sensor detects the at least one IR light emitting diode in the handle.

One embodiment is directed to a system that may include a user interface, sensor, receiver, and processing unit. The user interface may receive an input of a type of food. The sensor may detect a weight of a cooking vessel. The receiver may receive from the cooking vessel a property of the cooking vessel. The processing unit may determine a weight of the food in the cooking vessel from the sensed weight of the cooking vessel and the received property of the vessel. The received property of the vessel may include a tare weight of the vessel. In addition, the processing unit may determine a predicted cooking time based on the input food type and the determined weight of the food. In one embodiment, the may include a cooking vessel having a vessel handle. The vessel handle may have a memory and a transmitter disposed in the handle. The memory may store a vessel property and the transmitter may transmit the vessel property to the receiver. The vessel property may include a vessel size. In one embodiment, the processing unit may determine the predicted cooking time based the input food type, the weight of the food, and the vessel size. In one embodiment, the system may include a projector to project the user interface onto a display surface. In addition, the system may include a proximity sensor to detect whether a user is present in a particular area. The proximity sensor may provide a signal to a device indicative of whether the user is present in the particular area. The device may be communicatively coupled with the projector and the proximity sensor. The device may control the projector to scale the size of the projected user interface according to whether the user is detected in the particular area. In one embodiment, the system may include a sheet of glass-ceramic material having a top surface, at least one heating element, and an electrical conductor apparatus disposed parallel to the top surface in sheet of glass-ceramic. In addition, system may include a detection circuit coupled with the electrical conductor apparatus. The detection circuit may determine whether moisture is present on the top surface and may signal the processing unit if the detection circuit determines that moisture is present on the top surface. In one embodiment, the processing unit, in response to receipt of the moisture detection signal, causes an indication to be rendered in a user interface indicating that moisture is detected on the cooktop surface. In one embodiment, the indication indicating that moisture is detected on the cooktop surface is rendered in a user interface of a portable multifunction computing and communication device. In one embodiment, the processing unit, in response to receipt of the moisture detection signal, causes a command to be sent to an appliance to control the appliance.

Yet another embodiment is directed to an apparatus that includes an image sensor and a device. The image sensor may capture a reference image and one or more current images of a surface. A location of a cell on the surface may be positionally defined in the reference and current images. The device may be communicatively coupled with the image sensor. The device may determine whether pixels of the cell in the reference image and pixels of the cell in a current image differ. If the pixels of the cells in the respective images differ, the device may provide a signal. In one embodiment, the signal may include an indication of the location of the cell on the surface. In one embodiment, the apparatus may include a processing unit communicatively coupled with the device to receive the signal. The processing unit, in response to the signal, may enable a heating element corresponding with the location of the cell to be energized. In addition, the heating element may be configured to heat a particular one of two or more regions. In this context, the processing unit, in response to the signal, may enable a particular one of the two or more regions to be energized. In one embodiment, the device may determine whether a parameter exceeds a particular threshold. The parameter corresponds with the number of pixels of the cell in the current image that differ from corresponding pixels of the cell in the reference image. The device may provide the signal when the parameter exceeds the particular threshold. In one embodiment, the device ay identify a reference cooking vessel based on one or more of the size, shape, and value of the pixels of the cell in the current image.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a system for monitoring and controlling a cooking environment according to one embodiment.

FIG. 2 is front side view of a portable multifunction computing and communication device.

FIG. 3 is a side view of a cooking vessel and a cooking vessel lid according to one embodiment.

FIG. 4 is a top-side view of the cooking vessel and the cooking vessel lid of FIG. 1.

FIG. 5 shows cross-sectional side and top-side views of a handle of the cooking vessel of FIG. 3.

FIG. 6 shows cross-sectional side and top-side views of the handle of the cooking vessel lid of FIG. 3.

FIG. 7 is a front perspective view of a case, cooktop, and fume hood according to one embodiment.

FIG. 8 is a partially cross-sectional front view of the case and fume hood of FIG. 7.

FIG. 9 is a front perspective view of a cooktop according to one embodiment.

FIG. 10 is a first cross-sectional view of the cooktop of FIG. 9.

FIG. 11 is a second cross-sectional view of a cooktop of FIG. 9.

FIG. 12 is a front perspective view of a case, cooktop, and fume hood according to one embodiment.

FIG. 13 is a first partially cross-sectional front view of the case and the fume hood of FIG. 12.

FIG. 14 is a second partially cross-sectional front view of the cooktop and the fume hood of FIG. 12.

FIG. 15 is a floor plan of a cooking environment including the cooktop and the fume hood of FIG. 12.

FIG. 16 is a flow diagram of a process according to one embodiment.

FIG. 17 shows a cross-sectional top view of a cooktop according to one embodiment.

FIG. 18 shows cross-sectional side views of cooktops according to two embodiments.

FIG. 19 is a front perspective view of a case, cooktop, and fume hood having a camera mounted therein according to one embodiment.

FIG. 20 is a partially cross-sectional front view of the case and fume hood of FIG. 19.

FIG. 21 illustrates a plan view of the cooktop of FIG. 19.

FIG. 22 shows an exemplary frame captured by the camera of FIG. 19.

FIG. 23 is a flowchart of a method for determining the size and location of a cooking vessel on a cooktop according to an embodiment.

DETAILED DESCRIPTION

In the following detailed description of exemplary embodiments, reference is made to the accompanying drawings, which form a part of this description. In the several figures, like referenced numerals identify like elements. The detailed description and the drawings illustrate exemplary embodiments. Other embodiments may be utilized, and changes may be made to the exemplary embodiments, without departing from the spirit or scope of the subject matter presented here. In addition, any disclosed embodiment may be combined with any other disclosed embodiment whether or not this description expressly discloses the combination. The following detailed description is therefore not to be taken in a limiting sense, the scope of the claimed subject matter being defined only by the claims.

FIG. 1 is a block diagram of a system 38 for monitoring and controlling a cooking environment according to one embodiment. The system 38 may include one or more appliances 40. Exemplary appliances 40 include any type of appliance used for cooking, food preparation, or storage, such as a cooktop, oven, microwave oven, food processor, dish washer, refrigerator, cupboard, or pantry. In addition, in some embodiments exemplary appliances 40 include apparatus for washing or drying clothing, and entertainment devices such as televisions, media recorders and players, audio reproduction devices, and electronic games. In one embodiment, an appliance 40 may include one or more heating elements 52, and a unit 54 for turning heating elements 52 on and off, for controlling power supplied to a heating element 52, and for performing other heating element control functions. An appliance 40 may additionally include a transceiver 56 for communicating wirelessly or via electric wire or fiber optic cable with other devices. Moreover, in some embodiments an “appliance,” as the term is used in this description, may include a cooktop 50. The cooktop 50 may be a surface having one or more heating elements. Alternatively, the cooktop 50 may be a top surface (countertop) of a case or cabinet not having a heating element. A cooktop 50 may include a weighing scale 94 or a moisture detector 80. In addition, a cooktop 50 may include transceiver 92 for communicating wirelessly or via electric wire or fiber optic cable with other devices.

The system 38 may include one or more control devices 42. The control device 42 may include transceiver 58 for communicating wirelessly or via electric wire or fiber optic cable with other appliances, sensors, or devices. The control device 42 may include one or more processing units 60. A processing unit 60 may be CPU, DSP, hardware logic, state machine, or the like. A processing unit 60 may be operable to execute instructions, e.g., software. The control device 42 may include a memory 62. The memory 62 may store data or instructions for execution by a processing unit 60. The memory 62 may be a volatile or non-volatile memory. Exemplary memories 62 include flash memory chips and drives, floppy disks, memory cards, hard drives, RAMs, ROMs, EPROMs, compact disks, and magnetic tapes. The control device 42 may include a user interface 64. The user interface 64 may include devices for receiving input from a user, such as a keyboard, pointing device (e.g., mouse), joy stick, click wheel, touch screen, microphone, or camera. The user interface 64 may include devices for providing information to a user, such as a display screen, projector, speaker, or device for providing information to somatosensory (tactile) receptors of a user's skin, e.g., vibration, pressure. In one embodiment, a control device 42 may be mounted in a fixed location. In one embodiment, a control device 42 may be a portable multifunction computing and communication device.

FIG. 2 is front side view of a portable multifunction computing and communication device 96. The portable electronic device 96 may include a touch-sensitive display 98, which serves as a primary user interface 64. The portable device 96 may include one or more processing units, a memory, and a transceiver. The portable device 96 may employ its processing unit and memory to execute a variety of software applications. The portable device 96 may be enabled for wireless communication. The portable device 96 may be a cellular telephone and include well-known components, such as RF circuitry, that are required to support cellular telecommunications. In addition, RF and other circuitry may enable the portable device 96 to communicate with networks, such as the World Wide Web, a local area network, or a wide area network. The portable device 96 may use any necessary or suitable communication protocol or standard, including, but not limited to, the Global System for Mobile Communications, Enhanced Data GSM Environment, Bluetooth, high-speed downlink packet access, wideband code division multiple access, code division multiple access, time division multiple access, Wireless Fidelity (e.g., IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, or IEEE 802.11n), voice over Internet Protocol, WI-MAX, Short Message Service, email protocol, and instant messaging protocol. One advantage of using portable multifunction computing and communication device 96 as the control device 42 is that user may keep the device 42 on his person, enabling user access to a user interface wherever the user is located.

Referring again to FIG. 1, the system 38 may include one or more of a proximity sensor unit 65, a visible spectrum camera (or image sensor) unit 68, infrared spectrum camera (or image sensor) unit 70, and a visible spectrum projector unit 72. The proximity sensor 65, cameras 68, 70, and projector 72 may be mounted near to one another, e.g., in a fume hood. Alternatively, the proximity sensor 65, cameras 68, 70, and projector 72 may be mounted apart from each other. Each of the units 65, 68, 70, and 72 may include a controller (not shown), a transceiver (not shown), or both devices. Alternatively, a single controller and transceiver may be shared between two or more of the units 65, 68, 70, and 72. In one embodiment, the controller may include a capability to recognize and determine the location of an object captured by one of the cameras 68, 70. In one embodiment, the controller may include a capability to control operation one of the proximity sensor unit 65, a visible spectrum camera unit 68, infrared spectrum camera unit 70, and visible spectrum projector unit 72. In one embodiment, the controller may include a capability to process or interpret the output of one of the proximity sensor unit 65, a visible spectrum camera unit 68, and infrared spectrum camera unit 70. The controller may be an IC or a processing unit, and may include a memory. The transceiver may enable communication, wirelessly or via electric wire or fiber optic cable, between a unit 65, 68, 70, 72 or a controller, and a control device 42.

The system 38 may include one or more cooking vessels 46. A cooking vessel 46 may include a transceiver 74 for communicating wirelessly or via electric wire or fiber optic cable with other devices. In addition, a cooking vessel 46 may include any one or more of an infrared light emitting diode (“IR LED”) 76, a memory 78, or a thermionic power converter 82.

The system 38 may include one or more cooking vessel lids 48. A cooking vessel lid 48 may include a transceiver 84 for communicating wirelessly or via electric wire or fiber optic cable with other devices. In addition, a cooking vessel lid 48 may include any one or more of an IR LED 86, a motion sensor 88, and a thermionic power converter 90.

FIG. 3 illustrates a cooking vessel having a vessel body 100 and one or more vessel handles 102, and a cooking vessel lid 104 having one or more lid handles 106 according to one embodiment. The cooking vessel 100 may include one or more thermionic power converters 108 located on the vessel body 100 proximate to each vessel handle 102. In addition, the cooking vessel lid 104 may include one or more thermionic power converters 110 located on the lid proximate to the lid handle 106. FIG. 4 illustrates the cooking vessel 100 and the cooking vessel lid 104 of FIG. 3. As may be seen in FIG. 4, the vessel handles 102 and lid handle 106 may include one or more IR LEDs 112. An IR LED 112 may be disposed on a top side as shown in the figure or alternatively on a left, right, bottom, or other side. In one embodiment, the IR LED 112 emits radiation at a single frequency, e.g., 850 nm, or in a single band of frequencies.

FIG. 5 shows cross-sectional side and top-side views of a vessel handle 102 of the cooking vessel of FIG. 3. As may be seen in FIG. 5, a vessel handle 102 may include a transceiver 114, a memory 116, and a battery 118. A vessel handle 102 may include all of the transceiver 114, or a memory 116, battery 118, or any combination of one or two of the units 114, 116, and 118.

FIG. 6 shows cross-sectional side and top-side views of the lid handle 106 of the cooking vessel lid of FIG. 3. As may be seen in FIG. 6, a lid handle 106 may include a transceiver 114, a motion sensor 120, or a battery 118. A lid handle 106 may include the transceiver 114, motion sensor 120, battery 118, or any combination of one or two of the units 114, 118, and 120.

The transceiver 114 may transmit a property or condition of a vessel or a vessel lid to a receiver. The transceiver 114 may be one of the previously mentioned transceivers 74, 84. The memory 116 may store a vessel size, a vessel weight, a vessel capacity, a vessel type, or other parameter. In one embodiment, the transceiver 114 and memory 116 may be a known RFID (radio-frequency identification) device. The motion sensor 120 may be an angular rate or gyroscopic sensor that may be used for sensing rotation. The angular rate sensor 120 may sense rotation about one or more axes. Alternatively, the motion sensor 120 may be an acceleration sensor that senses linear acceleration along one or more axes of the sensor. In one embodiment, the motion sensor 120 may include both an angular rate sensor and an acceleration sensor. In an illustrative embodiment, both an acceleration sensor and angular rate sensor may be provided as part AH-6100LR, which includes a 3-axis QMEMS quartz gyro sensor and a 3-axis accelerometer in a single integrated circuit. The AH-6100LR part is available from Epson Electronics America, Inc., San Jose, Calif. In yet another embodiment, the motion sensor 120 may include a pressure sensor. The pressure sensor may positioned at the base of a handle so that a pressure sensing portion of the sensor is located within a cooking vessel so that is may sense pressure within the vessel.

The thermionic power converter 108 may exploit the known thermionic emission phenomena to generate electric power from a heat gradient between a vessel or vessel lid and a handle. The thermionic power converter 108 may include, in one embodiment, an array of p-type and n-type Bismuth Telluride pellets layered between a pair of ceramic substrates molded to fit the curves of the vessel body 100 and the cooking vessel lid 104. The thermionic power converter 108 (or battery 118) may provide an electric current to the IR LED 112, transceiver 114, memory 116, motion sensor 120, or other device integrated with or attached to a vessel or vessel lid. In addition, the thermionic power converter 108 may provide an electric current to the battery 118 to re-charge or top-up the battery 118. Advantages of including a thermionic power converter are that it may: (a) reduce the need for charging the battery 118 using an external power source; and (b) eliminate the need for battery 118 in some embodiments.

FIG. 7 is a front perspective view of a case 122, cooktop 124, and fume hood 130 according to one embodiment. The case 122 may be, for example, an enclosure for an appliance or a storage enclosure. The cooktop 124 may be all or a portion of a top surface of the case 122. The cooktop 124 may be made of a metal, glass-ceramic, plastic, wood, rock, or other suitable material. In one embodiment, the cooktop may be fully or partially transparent. The cooktop 124 may include one or more heating elements 52. The heating elements 52 may be, for example, of the gas, electric, IR halogen lamp, inductive, or other suitable type. A heating element 52 may be capable of heating only a fixed-size area, or may be capable of heating a variably-sized area. Alternatively, the cooktop 124 may not include a heating element 52. The cooktop 124 may include a user interface 128 for controlling the heating elements 52 or for performing or controlling other functions. The user interface 128 may present information to a user. One or more controls of the user interface 128 may take the form of a physical control, e.g., knob, button, switch, etc., or may be an image projected from a light projector.

FIG. 8 is a front view of the case 122 of FIG. 7. In addition, FIG. 8 includes a partially cross-sectional front view of the fume hood 130. As may be seen in FIG. 8, the fume hood 130 may include an infrared camera or image sensor 70. The infrared image sensor 70 may be an infrared camera having a pixel array of sensors. In one embodiment, the infrared image sensor 70 may include a filter so that it is sensitive to a single frequency, e.g., 850 nm, or one or more particular bands of frequencies. In one embodiment, the infrared image sensor 70 provides video output at a suitable frame rate, e.g., 30 frames per second. Any suitable resolution and frame rate may be used. In addition, it is not critical that the infrared image sensor 70 be disposed in the fume hood 130. In alternative embodiments, the infrared image sensor 70 may be mounted on or in a cabinet, a wall, a ceiling, or any other suitable location.

The infrared image sensor 70 and cooktop 124 may be installed at particular locations so that the infrared image sensor and cooktop are in a fixed spatial relationship with one another. A digital image captured by the infrared image sensor 70 may have fixed dimensions. For example, a frame may have dimensions of 640×480 pixels. Images captured by the infrared image sensor 70 may be mapped to the cooktop 124. The infrared image sensor 70 may capture infrared radiation emitted from one or more IR LEDs 112 disposed in a vessel handle 102 and lid handle 106. Accordingly, so long as the fixed spatial relationship between the infrared image sensor 70 and cooktop 124 is maintained, spatial locations of a vessel handle 102 and lid handle 106 on the cooktop may be determined from the pixel coordinates of the IR LED image in a captured frame. In some embodiments, the infrared image sensor 70 is positioned to one side of the cooktop 124, which may result in a keystone distortion effect. It is contemplated that a captured frame may be inverse-warped to prevent or minimize keystone distortion. From the sensed spatial location of one or more IR LEDs, a location of the cooking vessel may be determined. Further, the sensed spatial locations of one or more IR LEDs may be used to infer whether a cooking lid 104 has been placed on a cooking vessel.

In one embodiment, a vessel handle 102 or a lid handle 106 may include two or more IR LEDs. A particular number or pattern of IR LEDs may be used to designate and distinguish among different types and sizes of vessels, as well as different types and sizes of vessel handles. As one non-limiting example, the number of IR LEDs may designate vessel capacity, e.g., one IR LED corresponding with ½ liter, two IR LEDs corresponding with 1 liter, etc. In addition, in one embodiment an IR LED 112 may be disposed in a vessel handle 102 and lid handle 106 along with control circuitry to transmit a sequence of pulses of infrared light that represent specific binary codes. These binary codes may correspond to vessel size, vessel weight, vessel capacity, vessel type, or any other property or parameter stored in a memory integrated into a cooking vessel or vessel lid, e.g., memory 78, 116. In addition, a binary code may correspond with a sensed condition. A particular number or pattern of IR LEDs or a particular sequence of infrared light pulses may be captured by the infrared image sensor 70 and decoded by a controller associated with the infrared image sensor. Decoded information pertaining to a vessel or vessel lid property may be communicated to a control device along with other sensed parameters, such as vessel location. One advantage of determining the location of a cooking vessel on a cooktop is that power to a heating element may be inhibited unless a cooking vessel is detected in the same location as the heating element, making for a safer cooking environment. An advantage of determining the location a vessel lid is that detecting the presence of a vessel lid may be used to help determine cooking time in an automated fashion.

FIG. 19 is a front perspective view of a case 122, cooktop 124, and fume hood 130 illustrating an embodiment in which the visible spectrum camera 68 captures one or more visible images of a cooktop 124 having one or more heat elements 52. The cooktop 124 may include all or a portion of the top surface of case 122. FIG. 20 is a front view of the case 122 of FIG. 19. In addition, FIG. 20 includes a partially cross-sectional front view of the fume hood 130. As may be seen in FIG. 20, the visible spectrum camera 68 may be mounted in the fume hood 130. It is not critical, however, that the camera 68 be mounted in the fume hood 130. In alternative embodiments, the camera 68 may be mounted on or in a cabinet, a wall, a ceiling, or any other suitable location. The visible spectrum camera 68 may capture digital images at any suitable frame rate, e.g., 30 frames per second. The visible spectrum camera (or image sensor) 68 may include a CCD or CMOS image sensor having an array of sensor pixels. The visible spectrum camera 68 and cooktop 124 may be installed at particular locations so that the camera 68 and cooktop 124 are in a fixed spatial relationship with one another.

FIG. 21 illustrates a plan view of the cooktop 124. The cooktop 124 may include one or more heating elements 52. In one embodiment, a heating element may be configured to heat a particular one of two or more regions. For example, the heating element 52-1 may be configured to heat either region 220 or 222, the region 220 including the region 222. FIG. 22 shows an exemplary frame 224 captured by the image sensor 68. The digital image 224 may have fixed dimensions. For example, the frame 224 may be 600×600 pixels. The image 224 captured by the camera 68 may be mapped to the cooktop 124. So long as the fixed spatial relationship is maintained between the camera 68 and cooktop 124, the dimensions and position of the cooktop 124 may be mapped to pixels of the frame 224. As one example, the cooktop 124 may be 54×54 cm. Accordingly, points “a” and “c” of cooktop 124 may respectively correspond with pixel coordinates (0, 0) and (600, 600) of the captured image 224. Thus, the captured image 224 may be mapped to the cooktop 124, i.e., every pixel of the captured image corresponds with a coordinate location on the cooktop 124. Accordingly, the locations on the cooktop of heating elements 52 may be mapped to pixel coordinates in any captured image 224. In FIG. 22, regions of pixels in image 224 corresponding with the heating elements 52 on the cooktop 124 are identified by reference numbers 226. A region of an image 224 corresponding with heating element location 226 may be referred to in this description and the claims as a “cell.” The pixel coordinates of cells may be determined in a calibration process. The camera 68 may capture any physical object, such as a cooking vessel, that is located between the between the cooktop 124 and camera (or image sensor) 68. In some embodiments, the visible spectrum camera 68 may be positioned to one side of the cooktop 124, which may result in a keystone distortion effect. The captured frame may be inverse-warped to prevent or minimize keystone distortion.

FIG. 23 shows a flowchart of a method 230 for determining the size and location of a cooking vessel on a cooktop. In operation 232, the camera 68 captures a reference frame. The reference frame may be captured at a time when there are no physical objects between the cooktop 124 and image sensor 68. The reference frame may be captured as part of a calibration process. The reference frame may include a definition or identification in terms of pixel or other suitable coordinates of one or more cells of the frame 52 corresponding with heating element locations 226 on the cooktop 124. In operation 234, a cell is repeatedly scanned at periodic intervals. The operation 234 may include capturing two or more images at any suitable frame rate. The operation 234 may include continuously scanning the pixels of each cell in a current frame at periodic intervals, e.g., as each frame, or as two or more frames, are captured.

In operation 236, it may be determined whether pixels of the cell in the reference image and pixels of the cell in a current image differ. This difference may be determined in one or more ways. The operation 236 may include comparing pixels of a cell of the reference frame and of a current frame on a pixel-by-pixel basis. The operation 236 may include comparing values derived from the pixels of the particular cell in the reference and current frames, e.g., the respective average pixel values. The pixels of the frames may be defined in gray scale or color and the operation 236 may include comparing a particular component value of the pixels of the reference and current frames. For example, operation 236 may include comparing the green color channel for RGB pixels or the luminance channel for YUV pixels. The determination of whether pixels of the cell in the reference image and pixels of the cell in a current image differ may include determining whether the pixels values differ by an amount greater than a particular threshold. In one embodiment, the determination of whether pixels of the cell in the reference image and pixels of the cell in a current image differ may include determining whether the pixels of the cell in a current image substantially match a visual property of a cooking vessel, e.g., color, color pattern, or shape. In another embodiment, the determination of whether pixels of the cell in the reference image and pixels of the cell in a current image differ may include determining whether the pixels of the cell in a current image substantially match a visual property of an object other than a cooking vessel, e.g., the pixels of the cell in a current image may be determined to substantially match pixel values known to correspond with human skin color. In this embodiment, a determination that pixels of the cell in a current image substantially match a visual property of an object other than a cooking vessel may be treated as equivalent to a difference not being detected, i.e., an inference may be made that a cooking vessel is not present on the cooktop 124. If a difference is not detected, the method 230 returns to operation 234. If a difference is detected, it may be inferred, in one embodiment, that a cooking vessel is present on the cooktop 124 in the location corresponding with the cell, and the method 230 advances to operation 238.

In operation 238, the size or shape of the cooking vessel may be determined. In some embodiments, the operation 238 is optional. The operation 238 may determine size of the cooking vessel in one or more ways. The operation 238 may include determining a number or a percentage of pixels of a cell of the current frame having their values changed from the reference frame. In addition, it may be determined whether the number or percentage exceeds a particular threshold. For example, if 90 percent of pixels have changed values, it may be determined that a cooking vessel has a first size, and if 60 percent of pixels have changed values, it may be determined that a cooking vessel has a second size. Continuing the example, the first size may correspond with heat region 220 of heating element 52-1 in FIG. 21 and the second size may correspond with heat region 222. Of course, these exemplary percentages may vary. In one embodiment, the operation 238 may include detecting edges in the current frame between an area of the cell not having changed pixel values and an area having changed pixel values. Any known edge detection algorithm may be employed. One or more edges may be located. The pixel coordinates of located edges may be used to calculate the cross-sectional area (looking down onto the cooktop) occupied the cooking vessel. In addition, the pixel coordinates of located edges may be used to determine a cross-sectional shape of the cooking vessel. The calculated area or determined shaped may be compared with the areas of two or more reference cooking vessels to identify a reference cooking vessel most closely matching in size. A cooking vessel may be identified if it is determined to have a size or shape matching the identified reference cooking vessel.

In operation 240, a signal indicative of one or more of the size, location, or shape of the cooking vessel may be generated. Alternatively, the signal generated in operation 240 may include an identification of a cooking vessel. In some embodiments, the signal may be provided to a control device 42 or a heating element control unit 54. In operation 242, a control device 42, heating element control unit 54, or other device, in response to receiving the signal, may generate a control instruction for an appliance. In one embodiment, the control instruction may enable a heating element corresponding with the cell location to be energized. In one embodiment, a heating element may include two or more heat regions, e.g., heat regions 220 and 222 of heating element 52-1 in FIG. 21, and the control instruction may control a heating element so that only the region of the heating element corresponding with the detected size of the cooking vessel is energized. The enabling of a heating element or the controlling of the size of a heated region may include transmitting a signal, e.g., a control device 42 may transmit a signal to a heating element control unit 54. In some embodiments, the signal may be provided to a processing unit 60 determining a predicted cooking time (described below with reference to process 158) based at least in part on vessel size. It will be recalled that each of the units 65, 68, 70, and 72 may include a controller, and the operations 234-242 may be performed by a controller associated with the image sensor 68. Alternatively, the operations 234-242 may be performed by a processing unit 60. In an embodiment, the operations 234-242 may be performed in part by a controller associated with the camera 68 and in part by a processing unit 60. The method advantageously enhances safety and conserves energy. A heating element may only be energized if a cooking vessel is detected as being present on the heating element. In addition, an identification of a cooking vessel may be used in determining cooking time in an automated fashion.

FIG. 9 is a front perspective view of a cooktop 124 according to one embodiment. The cooktop 124 may be a top surface of the case 122 and may include one or more heating elements 52 and a user interface 128. In one embodiment, a cooktop 124 or other portion of the top surface of the case 122 may include one or more weighing scales 134 or 136. In one embodiment, a weighing scale 134 may be located apart from a heating element 52. Alternatively, a weighing scale 136 may be located with a heating element 52, e.g., concentrically with a heating element. FIG. 10 is a first cross-sectional view of the cooktop of FIG. 9 taken along line 6-6 showing construction of a weighing scale 134 located apart from the heating elements 52. As shown in FIG. 10, a weighing scale 134 may include an area of the top surface of the case 122 that is thinner than the top surface 124. By providing a thin area of the top surface 124, that area may be made deformable, flexible, or bendable. In one embodiment, the thin area of the top surface may be made of metal or plastic. In one alternative, the area corresponding with the weighing scale 134 may be a distinct, separately movable part of the cooktop 124 so that it is unnecessary that the weighing scale 134 area be formed from a flexible material. In addition, where the weighing scale 134 is a distinct, separately movable part, it need not include an area thinner than the top surface 124. On the underside of the weighing scale 134 area, one or more pressure sensors 138 may be mounted.

FIG. 11 is a second cross-sectional view of the cooktop of FIG. 9 taken along line 7-7 showing weighing scales 136 located concentrically with two of the heating elements 52. The heating elements 52 shown in FIG. 11 are of the inductive type, including inductive coils 140. It should be noted that it is not essential that a weighing scale 136 be located concentrically with a heating element 52. Any suitable non-concentric arrangement may be employed. The weighing scales 136 of FIG. 11 may be constructed according to one of the designs described above. In alternative embodiments, a weighing scale 136 may be located with an electric, gas or other type of heating element. In any embodiment of a weighing scale 134, 136, the weighing scale may be coupled with a transmitter, e.g., transceiver 92, which may be employed to transmit a weight sensed by the weighing scale to a receiver, such as a control device 42.

The cooktop 124 shown in FIG. 9 may be employed to perform a process 158 as follows. Referring to FIG. 16, a type of food may be input using the user interface 128 (operation 160). The cooking vessel 100 containing the food to be cooked may be placed on either the weighing scale 134 or 136 and the gross weight of the vessel and contents may be obtained (operation 162). The weighing scale 134 or 136 transmits the stored tare weight to a receiver, e.g., control device 42. The memory 116 in the handle 102 of the cooking vessel 100 may store the tare weight of the vessel. The transceiver 114 in the handle 102 of the cooking vessel 100 may obtain a stored tare weight and may transmit the stored tare weight to a receiver (operation 164). In one alternative, memory 116 stores a vessel size and transmitter 114 transmits the stored vessel size to the receiver. The receiver may be coupled with a processing unit and a memory storing a program of instructions. The processor may be additionally coupled with the user interface 128. In one embodiment, gross and tare weights are transmitted to the control device 42, which includes the processing unit and memory storing a particular program of instructions. The processing unit executes the program of instructions to determine a weight of the food in the cooking vessel 100 from the sensed gross weight of the cooking vessel and the stored tare weight of the vessel (operation 166). In addition, the processing unit may determine a predicted cooking time based on the input food type and the weight of the food (operation 168). In addition, in one embodiment the processing unit may determine a predicted cooking time based on food type, food weight, and vessel size. In an alternative embodiment, the memory 116 in the handle 102 of the cooking vessel 100 may store at least one property of the vessel and the transceiver 114 in the handle 102 of the cooking vessel 100 obtains the at least one stored property and transmits the stored property to a receiver. A property may be transmitted using any technique described in this specification. In addition, in lieu of transmission, a property may be sensed using any technique described in this specification. In addition, in one embodiment the processing unit may determine a predicted cooking time based on food type, food weight, vessel size, and the presence or absence of a vessel lid. Any of this information may be detected or sensed using any embodiment disclosed in this description. Further, any of this information may be input via a user interface. The processor may time a cooking process, monitoring and comparing elapsed time with predicted cooking time (operation 170). When elapsed time equals predicted cooking time, the processor may signal completion of the cooking process (operation 172). In one embodiment, the signaling of the completion of the cooking process may include displaying or playing a visual or audible signal of completion for a user. Alternatively, the signaling of the completion of the cooking process may include presenting a tactile signal of completion to a user. The signal may be in the form of an alert, an alarm, or a message for a user. The signal may be rendered in a user interface. In one embodiment, the signaling of the completion of the cooking process may include sending a command to control a cooking appliance. For example, the signal may be sent to transceiver 56, which relays the signal to heating element control unit 54. The heating element control unit 54 may cause power to a cooking element 52 to be reduced or turned off. Advantages of the process 158 are that a user need not determine or monitor cooking time, and need not turn off the appliance once the food is cooked.

FIG. 12 is a front perspective view of the case 122, cooktop 124, and fume hood 130 according to one embodiment. The cooktop 124 may be all or a portion of a top surface of the case 122. The cooktop 124 may include two or more heating elements 52. The cooktop 124 may include a user interface 128. In one embodiment, a second user interface 142 is provided. The second user interface 142 may be an image projected from a light projector 144 onto a surface. The second user interface 142 may be rendered in more than one size, e.g., it may be rendered in a first size exemplified by user interface 142-1 (FIGS. 12 and 13) and in a second size exemplified by user interface 142-2 (FIG. 14). The projection surface may be a vertical surface, such as wall 143 or the side of an appliance. Alternatively, the projection surface may be a horizontal surface, such as the top surface of the case 122. In one embodiment, the projection surface may lie in a plane that is neither horizontal nor vertical. For example, the projection surface may lie in a plane that makes a 45 degree angle with the horizontal. The second user interface 142 may present information of any desired type to a user. For example, the second user interface 142 may be a display of symbolic or iconic information indicating which heating elements 52 are turned on, the power level of a heating element, or an analog timer. The second user interface 142 may also be or include a display of textual information, such as numerals of a digital timer or instructions of a food preparation recipe. In addition, in one embodiment the second user interface 142 may be employed to accept input for controlling the heating elements 52 and performing other functions. As one non-limiting example of first and second sizes, the second user interface 142-1 may include text having 14 point type while the second user interface 142-2 may include text having 24 point type.

FIG. 13 is a front view of the case 122 of FIG. 12. In addition, FIG. 13 includes a first partially cross-sectional front view of the fume hood 130. As may be seen in FIG. 13, the fume hood 130 may include the visible spectrum light projector 144 and a proximity detector 146. It is not critical that the light projector 144 be disposed in the fume hood 130. In alternative embodiments, the light projector 144 may be mounted on or in a cabinet, a wall, a ceiling, or any other suitable location.

The proximity detector 146 senses proximity of a person to a particular area, e.g., a cooktop 124. Referring to FIG. 15, the proximity detector 146 may sense whether a user is within an area 150 directly in front of the case 122. In one embodiment, the proximity detector 146 may be an active infrared sensor, e.g., the proximity detector includes an infrared emitter and an infrared sensor. In another embodiment, the proximity detector 146 may include a passive infrared proximity detector. In alternative embodiments, the proximity detector 146 may include a visible spectrum optical detector or an ultrasonic range detector. In one embodiment, the proximity detector 146 may include the infrared camera or image sensor 70 and image recognition logic for identifying a user and the spatial position of the user. It is not critical that the proximity detector 146 be mounted in the fume hood 130. In alternative embodiments, the proximity detector 146 may be mounted on or in a cabinet, a wall, a ceiling, or any other suitable location.

In one embodiment, the size of the second user interface 142 may be automatically adjusted according to whether the sensed position of a human user is in an area near the cooktop 124, e.g., area 150. See FIG. 15. If a user is in the area 150, the proximity detector 146 may transmit a signal to a control device 42. In response to receipt of the signal from the proximity detector 146, the processing unit 60 may cause the projector 144 to project a user interface 142-1 (having the first size) onto a display surface. If a user is not in the area 150, e.g., the user is in area 152, then, in response to the absence of a signal from the proximity detector 146, the processing unit 60 may cause the projector 144 to project a user interface 142-2 (having the second size) onto the display surface. FIG. 14 is a second front view of the case 122 of FIG. 12. In addition, FIG. 14 includes a second partially cross-sectional front view of the fume hood 130. In one embodiment, a second projected user interface 142-2 is provided. The second user interface 142-2 is a scaled replica of the user interface 142. FIG. 15 is a floor plan of a cooking environment including the cooktop and the fume hood of FIG. 12 illustrating one example of the areas 150 and 152. An advantage of automatically scaling a user interface according user proximity is that it enables a user to read and understand the user interface from any location in a food preparation area.

FIG. 17 shows a cross-sectional top view of a cooktop 124-1. The cooktop 124-1 may include heating elements 52 and one or more electrical conductor arrangements 200-1, each having first and second spaced-apart electrodes 210, 212. The electrical conductor arrangement 200-1 may include one or more capacitors for sensing the presence of moisture on the top surface 202 of the cooktop 124-1. The first and second electrodes 210, 212 may be substantially parallel one another, functioning as oppositely charged electrodes of the one or more capacitors. In addition, multiple instances of the first and second electrodes 210, 212 may be provided in distinct regions of the cooktop 124-1. An instance of the first and second electrodes 210, 212 may be located so that it is spatially associated with a particular heating element. The first and second electrodes 210, 212 may be linear as shown in FIG. 18. However, this is not critical as the first and second electrodes 210, 212 may be provided in any desired shape or pattern, e.g., circular, square grid, zig-zag. In one embodiment, the first and second electrodes 210, 212 may be circular, with an instance located concentrically with respect to each heating element 52.

FIG. 18 shows cross-sectional side views of the cooktop 124-1, and a second cooktop 124-2. As may be seen from FIG. 18, the electrical conductor arrangement 200 is disposed between a top surface 202 and a bottom surface 204 of the cooktops 124-1, 124-2. (It will be understood that the top surface 202 is the surface presented to a user when operating the appliance and upon which cooking vessels may be placed.) The electrical conductor arrangement 200 may be parallel to the top surface 202 and may be positioned below but relatively close to the top surface 202. For example, the top and bottom surfaces 202, 204 of a cooktop may be 25-30 mm apart while the closest edge of electrical conductor arrangement 200 may be within 2 mm from the top surface 202. In one embodiment, the electrical conductor arrangement 200 may be positioned on the top surface 202. Each of the electrical conductors 200 includes a connector. The electrical conductor arrangement 200-1 includes a connector 206 that is parallel to top surface 202. The electrical conductor arrangement 200-2 includes a connector 208 that is perpendicular to top surface 202, and may extend either upward or downward, as shown.

The cooktop 124-1, 124-2 may be formed from a glass-ceramic or other suitable material. The electrical conductor arrangement 200 may be formed from a sheet or wire of any suitable electrically conductive material, such as but not limited to copper. In one embodiment, the electrical conductor arrangement 200 may be introduced into the glass-ceramic during the process of manufacturing the glass-ceramic cooktop 124, e.g., while the glass-ceramic material is in a non-solid state. In an alternative embodiment, the glass-ceramic cooktop 124 may be comprised of two layers, the electrical conductor arrangement 200 being sandwiched between the two layers. In this embodiment, the two layers may be bonded together chemically, mechanically, or in another suitable manner.

The connectors 206, 208 of the electrical conductor arrangements 200-1, 200-2 may be electrically coupled with a drive circuit (not shown). In one embodiment, the drive circuit may include an oscillating circuit that is employed to apply an excitation signal to the electrical conductors and a measurement circuit to measure a frequency, the frequency being proportional to capacitance. Alternatively, the drive circuit may include an impulse circuit that is employed to apply a voltage impulse to the electrical conductors and a measurement circuit to measure an output voltage, the output voltage being proportional to capacitance. In other embodiments, any known drive circuit for sensing a change in capacitance may be employed. The capacitance sensed by a drive circuit may cause a signal indicative of whether or not moisture is present on the cooktop to be provided to a control device 42.

A control device 42 may receive a signal from the drive circuit indicative of whether or not moisture is present on the cooktop, the presence of moisture being inferred from a change in capacitance. In response to this signal, the control device 42 may signal a user that moisture is present on the cooktop or that food cooking on the cooktop has boiled over. The signal provided to the user may include displaying or playing a visual or audible signal, or presenting a tactile signal to the user. The user signal may be in the form of an alert, an alarm, or a message for a user. The user signal may be rendered via any suitable user interface. In one embodiment, the signal sent by the control device 42 may be sent to an appliance and may include a command to control the appliance. For example, the signal may be sent to transceiver 56, which relays the signal to a particular heating element control unit 54 spatially associated with the detected moisture. In response to the signal received from the control device 42, the heating element control unit 54 may cause power to a cooking element 52 to be reduced or turned off. An advantage of providing moisture detection in a cooktop is that it allows a user to be automatically alerted of a boil over condition without regard to the user's location. In addition, it provides the advantage of automatically controlling a heating element to eliminate the boil over condition.

As used in this description, the term “transceiver” may include only a transmitter, only a receiver, or both a transmitter and a receiver.

The methods and variations on these methods described above may be implemented in hardware, software, or in a combination of hardware and software. Software for execution by processing unit to implement all or part of any method described above may stored in any of the memories described in this specification.

It should be understood that the embodiments described above may employ various computer-implemented operations involving data stored in computer systems. These operations are those requiring physical manipulation of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. Further, the manipulations performed may be referred to in terms, such as producing, identifying, determining, or comparing.

Any of the operations described in this specification that form part of the embodiments are useful machine operations. As described above, some embodiments relate to a device or an apparatus specially constructed for performing these operations. It should be appreciated, however, that the embodiments may be employed in a general purpose computer selectively activated or configured by a computer program stored in the computer. In particular, various general purpose computer systems may be used with computer programs written in accordance with the teachings herein. Accordingly, it should be understood that the embodiments may also be embodied as computer readable code on a computer readable medium.

A computer readable medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable medium include, among other things, flash drives, floppy disks, memory cards, hard drives, RAMs, ROMs, EPROMs, compact disks, and magnetic tapes.

Although the present invention has been fully described by way of the embodiments described in this specification with reference to the accompanying drawings, various changes and modifications will be apparent to those having skill in this field. Therefore, unless these changes and modifications depart from the scope of the present invention, they should be construed as being included in this specification. 

1. A cooking vessel, comprising: a vessel handle; a memory disposed in the vessel handle to store a vessel parameter; a transmitter disposed in the vessel handle to transmit the vessel parameter; and a thermionic power converter to provide electrical energy to the memory and transmitter.
 2. The cooking vessel of claim 1, further comprising at least one IR light emitting diode disposed in the vessel handle, wherein a location of the cooking vessel is determined with the infrared image sensor.
 3. The cooking vessel of claim 1, further comprising: a cooking vessel cover; a sensor disposed in the cooking vessel cover to detect a boil condition in the cooking vessel; a transmitter disposed in the cooking vessel cover to transmit a message indicative of a detected boil condition.
 4. The cooking vessel of claim 3, wherein the sensor includes a gyroscopic sensor.
 5. The cooking vessel of claim 3, wherein the sensor includes an acceleration sensor.
 6. A cooking vessel, comprising: a handle; and at least one IR light emitting diode disposed in the handle, wherein a location of the cooking vessel is determined with an infrared image sensor.
 7. The cooking vessel of claim 6, further comprising a thermionic power converter to provide electrical energy to the at least one IR light emitting diode.
 8. The cooking vessel of claim 6, wherein the at least one IR light emitting diode includes at least two IR light emitting diodes arranged in a pattern, the pattern corresponding with a particular one of two or more cooking vessels.
 9. The cooking vessel of claim 6, wherein the at least one IR light emitting diode emits a particular sequence of IR light pulses identifying the cooking vessel
 10. The cooking vessel of claim 6, wherein the at least one IR light emitting diode emits radiation at a single frequency.
 11. The cooking vessel of claim 6, further comprising: a cooking vessel cover; a sensor disposed in the cooking vessel cover to detect a boil condition in the cooking vessel; and a transmitter disposed in the cooking vessel cover to transmit a message indicative of a detected boil condition.
 12. The cooking vessel of claim 11, wherein the sensor includes a gyroscopic sensor.
 13. The cooking vessel of claim 11, wherein the sensor includes an acceleration sensor.
 14. The cooking vessel of claim 6, further comprising: a cooking vessel cover including a vessel cover handle; and at least one IR light emitting diode disposed in the vessel cover handle, wherein the presence of the cooking vessel cover is determined with the infrared image sensor.
 15. A system, comprising: a user interface to receive an input of a type of food; a sensor to detect a weight of a cooking vessel; a receiver to receive from a cooking vessel a property of the cooking vessel; and a processing unit to determine a weight of the food in the cooking vessel from the sensed weight of the cooking vessel and the received property of the vessel, the received property including a tare weight of the vessel, and a predicted cooking time based on the input food type and the weight of the food.
 16. The system of claim 15, further comprising: a cooking vessel having a vessel handle; a memory disposed in the vessel handle to store a vessel property; and a transmitter disposed in the vessel handle to transmit the vessel property to the receiver.
 17. The system of claim 16, wherein the vessel property includes a vessel size and the processing unit determines the predicted cooking time based the input food type, the weight of the food, and the vessel size.
 18. The system of claim 15, further comprising: a projector to project the user interface onto a display surface; and a proximity sensor to detect whether a user is present in a particular area and to provide a signal to a device indicative of whether the user is present in the particular area; and the device, communicatively coupled with the projector and the proximity sensor, to control the projector to scale the size of the projected user interface according to whether the user is detected in the particular area.
 19. The system of claim 18, wherein the display surface is a surface of the appliance.
 20. The system of claim 18, wherein the display surface is a surface adjacent to the appliance.
 21. The system of claim 15, further comprising: a sheet of glass-ceramic material having a top surface; at least one heating element; an electrical conductor apparatus disposed parallel to the top surface in the sheet of glass-ceramic; and a detection circuit coupled with the electrical conductor apparatus, the detection circuit to determine whether moisture is present on the top surface and to signal the processing unit if the detection circuit determines that moisture is present on the top surface.
 22. The system of claim 21, wherein the processing unit, in response to receipt of the moisture detection signal, causes an indication to be rendered in a user interface indicating that moisture is detected on the cooktop surface.
 23. The system of claim 21, wherein the processing unit, in response to receipt of the moisture detection signal, causes an indication to be rendered in a user interface of a portable multifunction computing and communication device indicating that moisture is detected on the cooktop surface.
 24. The system of claim 21, wherein the processing unit, in response to receipt of the moisture detection signal, causes a command to be sent to an appliance to control the appliance.
 25. An apparatus, comprising: an image sensor to capture a reference image and one or more current images of a surface, a location of a cell on the surface being positionally defined in the reference and current images; and a device communicatively coupled with the image sensor, the device to determine whether pixels of the cell in the reference image and pixels of the cell in a current image differ and to provide a signal if the pixels of the cells in the respective images differ.
 26. The apparatus of claim 25, wherein the signal includes an indication of the location of the cell on the surface.
 27. The apparatus of claim 26, further comprising a processing unit communicatively coupled with the device to receive the signal, the processing unit, in response to the signal, to enable a heating element corresponding with the location of the cell to be energized.
 28. The apparatus of claim 27, wherein the heating element may be configured to heat a particular one of two or more regions and the processing unit, in response to the signal, enables a particular one of the two or more regions to be energized.
 29. The apparatus of claim 25, wherein the device determines whether a parameter corresponding with the number of pixels of the cell in the current image that differ from corresponding pixels of the cell in the reference image exceeds a particular threshold, and provides the signal when the parameter corresponding with the number of pixels of the cell in the current image that differ from corresponding pixels of the cell in the reference image exceeds the particular threshold.
 30. The apparatus of claim 29, wherein the device identifies a reference cooking vessel based on one or more of the size, shape, and value of the pixels of the cell in the current image. 